In general, electrical image displaying is a process of decomposing an image to small units and displaying them on display device screen separately. When the decomposed unit is small enough, these separate components on display screen may no longer be separated by human eyes and thus constructs the complete, smooth image on the device screen. These decomposed small units of an image are called pixels, an independent structure on device screen that displays an image pixel is called a pixel cell, or a cell in short.
A pixel may be monochromatic or a number of different colors. To construct a colored pixel, a pixel is further decomposed into primary color components. Primary colors are a set of colors that any color in the color space may be generated from them by mixing different volumes of primary colors together in theory. There are different primary color sets. One of the popular primary color set is red, green, and blue for example.
After chosen primary color set, a pixel cell is further divided into multiple sub cells, call color cells, each color cell represents one primary color in the chosen primary color set. By controlling light volumes from each color cell in a pixel, a pixel may have many different colors and brightness levels.
Humans perceive the real world through two views obtained by both eyes. The human brain interprets them, generates the space distance from them and forms a 3-D vision. A 3-D display simulates this observing process. The different eyes of an observer view slightly different images like human observes the real world. The images observed by left and right eyes are called the left image and right image, they are also referenced as a stereo image pair.
Liquid Crystal (LC) is a type of material has one common property: its molecules in their natural status are arranged in a loosely ordered fashion with their long axis parallel; When they come into contact with a finely grooved surface, molecules line up parallel along grooves; When an electric field is applied on it, the molecules rearrange themselves with the long axis direction along with the electric field direction.
When light pass through LC, the light oscillation direction follows the long axis direction of the LC molecules. When LC is sandwiched between two plates with the opposite surfaces finely grooved and the groove directions of two plates is in a certain degree, Light oscillation direction changes the same degree when light passes through the LC molecules. When an electric field is applied on the LC in the direction of light, the light oscillation direction maintains unchanged.
This LC property is used to form a regular liquid crystal display (LCD). FIG. 1 is a section view of Prior Art functional LCD panel structure. The first polarizer film 110 converts light from backlight unit 101 to polarized light with its single oscillation direction parallel to polarized direction of the first polarizer film 110. The alignment layer surface is finely grooved and the groove directions of the two plates are in a certain degree. The polarization direction of second polarizer film 111 and first polarizer film 110 is arranged in certain degree so that the polarized light passing through LC 119 changes its oscillation direction to a degree that is perpendicular to the polarization direction of the second polarizer film 111 and be completely blocked. This value of degrees between two polarizer films depends on the LC material used.
For twisted nematic (TN) LC, it is 90 degrees when groove direction of alignment layer 117 and 118 is perpendicular, as an example. Electrode layers 115 and 116 provide electrical field controls that drive LC molecules twisting level so that the strength of light passing through varies from complete through to complete block. With color filter 114, it provides different color and brightness volume on each color cell, thus different colors on each pixel cell, and thus forms a complete image on the screen. A LCD panel 102 is a structure that provides light-switching functionalities controlled by electrical signals on every color cells or pixel cells to form images when light passes through it.
FIG. 2 is a section view of functional Dual Polarizing Filter (DPF) structure, which was disclosed in Provisional U.S. Patent Application 60/558,898, and U.S. patent application Ser. No. 11/092,889, both of which are incorporated herein by reference. It comprises first substrate 123 and second substrate 122 set apart, optional color filter 124, signal control electrode layer 125, first alignment layer 128, LC layer 129, second alignment layer 127 and optional common electrode layer 126 are layered between the two substrates. The detail structure of matrix circuit, transparent pixel electrodes and switchers such as TFT or the like that constructs signal control electrode layer 125 is not shown. The spacer used to maintain the consistent thickness of LC layer 129 and other functional critical layers are not shown either. A Dual Polarizing Filter 103 is a structure that provides light-twisting functionalities controlled by electrical signals on every color cell, which was referenced as a unit in the previous patent applications.